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Against Mystery

Isn’t it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too? – Douglas Adams

This post began as a response to Jenny’s article, but it got a little tangential.

I just watched the first in a series of programmes on the history of the Bible, presented by the novelist Howard Jacobson:  “Creation”

I’m wary of entering religious discussions, because they rarely, if ever, go well unless you’re already in agreement with the person with whom you’re discussing.

Nevertheless, I feel, as an atheist, somewhat denigrated by that programme. I feel almost cast as if I was an robotic automaton, in thrall to the iron certainty of my science, of “mere fact”, so blind to art and literature that I would come out of a performance of King Lear and wonder if the man really existed.

They complain about the so-called “New Atheists” campaigning against the straw-men of religious believers; I say that they’re talking about straw-men atheists.

Personally, I love myth, and legend. If we weren’t called atheists, I would love to call ourselves Prometheans, stealing fire from the jealous gods for the benefit of Man. I love reading the modern myths of an author like Neil Gaiman, spinning stories of Dream and Death. I love the musings of Hamlet on death and existence, and I read the philosophy of Sartre and Nietzsche, trying to get to the nature of existence and the human condition.

I see no reason why Genesis should be venerated over and above, say, the Theogony, or the creation tales of the Shintoists, or any other work of literature. The artistry is incredible, but I see no reason why I should be compelled to find truth in it, other than the truths it reveals about the people who wrote these stories.

I find myself most agreeing with the wonderful A.C. Grayling; people wrote these stories to find agency, meaning, in a disordered universe. There’s a good reason most of them start with the division of disorder into order! Jacobson recoils when the ancients were described as ignorant, as if it’s a perjorative; the truth is that they were, they simply did not know then what we know now, after years of struggle and careful experiment. Newton was ignorant of quantum mechanics; that’s hardly a slight on his genius.

As usual, the non-scientist’s misunderstanding of the nature of science is dredged up; that we possess a cast-iron certainty, blind to everything else.

This is bollocks of the absolute highest order. Science is doubt. Science is questioning, science is about looking at the universe and admitting that our understanding of it is fragmentary and incomplete, and that we should rectify that.

Take, for example, particle physics. We have this awesome theory, the Standard Model, that describes to a truely astounding accuracy the behaviour and interactions of every known fundamental particle. It’s a staggering intellectual achievement. We’re not sure about it yet; one component of it (the Higgs particle) is still as yet unobserved, and we know that the theory will break down at higher energy scales.

This isn’t blind certainty, it’s a diligent quest to know and understand more.

What men like Jacobson and his hero, Keats, fear is that all the important things in life lie in the gaps between our knowledge, and that as science carries on it will stitch up those gaps one by one until there is nothing transcendent left in the universe, because something can be transcendent only by being unknown and mysterious, clouded in haze. They fear that the God-of-the-Gaps will be driven out.

One, if your faith is only in a God-of-the-Gaps you deserve to be driven out. What does your faith really mean if it must be constantly modified so that it isn’t obliterated by the encroaches of science? The only way I can see that ending is in a God that has been so declawed as to be nothing more than a vague spirit, not even finding a refuge beyond space and time or after death as he does now.

Two, they ignore the beauty in the truth that science reveals. The inconceivable age of the universe, the bizarre era of the condensed quark-gluon plasma, the last fading microwave echos of the time the universe was opaque, the twisted time and space of a black hole, the wonderful mad complexity of life, the nuclear-powered twisting fury of the Sun, the emptiness in the heart of the atom… the examples of wonderful ideas that come out of science and mathematics are innumerable.

Keats blamed Newton for destroying the poetry of a rainbow by explaining it; I say that a rainbow is still as beautiful today, and I think more so because I understand it; I understand how light is refracted through a drop of water, reflecting off the back surface of the spherical drop. I think that’s beautiful. I think that the solutions of the Maxwell equations of a dielectric interface that describe the reflection of light are beautiful.

Jacobson and Keats would have us give up. To throw our hands in the air, and declare that some things should be unknown, un-sought for. Thank goodness nobody listened to Keats; I dread to think where we would be if Newton’s ideas had been suppressed. This is why we should never, ever give in to irrationality. Some things are far too important.

I think our own origins as creatures who have evolved and transcended our ancestors, who have toiled against the odds to create our civilisation and our knowledge is a far more beautiful story than any that could be told by a religion, and I feel that it is ever the better because it’s what actually happened.

The title of this post is a reference to John Bell’s paper “Against Measurement” which you can read if you happen to be on a University campus. It is a piece of essentially scientific doubt on the admittedly dubious interpretation of the concept of measurement in the foundations of quantum mechanics.

Of the Sun and Streetlights

Did you know that we can measure the magnetic field on the surface of the Sun?

That is something I find absolutely marvellous, that we can measure magnetism on something over 92 million miles away from here, on a surface that’s over 5000 degrees celsius. It’s one hell of a trick, for sure.

It’s accomplished by using a phenomenon called the Zeeman effect, and just a pinch of quantum mechanics. Electrons orbiting the nucleus are only allowed in a set of distinct energy levels, so they can only absorb energy to jump from one level to another. Photons of light have only a certain energy related to their wavelength (or colour); this means that to jump from one given energy level to another, only a very specific colour of light will do.

This means that when certain colours of light hit that atom, they’ll be absorbed and cause electrons to jump into higher energy levels. This causes certain colours of light to be missing when you look at a rainbow (or spectrum) of the light. You can calculate where these lines would be from quantum mechanics. This is how we know what the Sun is made from, for instance.

Now, when you add a magnetic field to the mix, things get a little more interesting. The magnetic field affects the orbit of the electrons, and splits one energy level into many more. This means that there are now more ways for electrons to jump from one level to another, so your neat little spectral absorbtion line will split into many lines: this is the Zeeman effect. You can tell from how much the line has split what the magnetic field strength is.

All these results can be calculated from quantum mechanics, and the Zeeman effect works just as well here on the ground as it does in the Sun. It’s brilliant!

Extra: Spectral lines work in reverse, too. Electrons in higher energy levels in an atom can only lose energy and go into a lower level by emitting a photon of a precise colour. Streetlights, for instance, work by exciting electrons in sodium, which then emit a photon of a very particular orange colour as they drop down into a lower level. This means that streetlights are almost exactly monochromatic (i.e. a single colour).

Weariness

So I’m roughly half-way through the exam season, five down, four to go.

Some of them have gone well, others not so well, others were going well until I found myself running out of time, started panicing and ignored the obvious answer…

Anyways, all in all, it’s been pretty miserable so far, and it really doesn’t do wonders for morale. I really just want this to be over, because this whole experience is just making me feel like crap, and I’m pretty damned sick of it.

Right now, I’m supposed to be revising Plasma Physics, because the exam’s tomorrow and for the life of me I have no idea what he’s doing using the Bennett relation to derive the Pease-Braginskii current, and I really need this exam to go well. For a whole bunch of reasons.

At least there’s only 4 left! Plasma I think is generally going to go well, then on Friday there’s Comprehensive II, the sequel to the exam that made us all want to commit suicide the first time around, Dynamical Systems & Chaos on Tuesday, which could be pretty unpleasant, and then Foundations of Quantum Mechanics on Thursday which I think will be pretty good too, so should form a pleasant wind-down. Hopefully.

I’m really not looking forward to results day.

Anyways, back to the physics of the Z-pinch…

The Hard Slog Ahead

Once again I’ve managed to forget that this blog isn’t just to write articles about stuff, it’s also just to write vaguely long-form about where I’m at, and where I’ve been. So, here goes.

Since we last met, I attended the Fairtrade Society AGM, at which I failed to get elected as treasurer. I still believe in the cause, though, so I’m actually changing my buying decisions where there is a Fairtrade alternative. Which is actually kinda peculiar! There was also the Fencing annual dinner, proceeded by the shaving of the president, which was pretty funny. Some people weren’t too gentle with the clippers.

Namih gets shaved

The deadline for MSci project bids rolled in, and with any luck my project will be on using a tree code to simulate plasmas in which collisional effects between particles can’t be neglected (e.g. in a very high density plasma) and provides an O(N log N) computation time as opposed to O(N^2) for naive particle-particle interactions. If you didn’t understand what I just said, never mind.

Coming up, my exams start on May 18th, so I basically have to start hitting the revision really hard and cram a whole bunch of knowledge into my head over the next few weeks. It’s going to be quite a ride. Next term there aren’t really any lectures apart from a single revision lecture for each course, so it’s a straight run-up to the exams, and then we’re pretty much free after that. We have to start preparing for a literature review for the MSci project, which I assume translates as “Raid all the books from the library that are relevant to your project, and then read them”.

My family’s going to come up for a day, and we’re going to see We Will Rock You, so that should be an interesting diversion. I should also be Fencing every Wednesday, so that should keep me active.

Then, once that kerfuffle is all over, there’s the Summer Ball, which should be an awesome wind-down to the year. I honestly can’t believe we’re already at this point again. The rapidity of it all is kinda scary, as are some of the implications of this year being over, like a bunch of my friends finishing their degrees. It’s gonna be weird.

Revision is pretty much the worst thing ever.

I really, really dislike revision. It’s not so bad when it’s something that’s reasonably interesting, like Quantum Mechanics or something, but trying to bludgeon my brain into learning Thermodynamics in this kind of heat is frankly just horrific and painful, and I want it to go away and leave me alone.

My exams are:

  • Thermodynamics & Statistical Physics
  • Quantum Mechanics
  • Applications of Quantum Mechanics & Electrons in Solids
  • Fourier Methods, Differential Equations, & Statistics of Meausurement
  • Mathematical Methods
  • Electromagnetism & Optics

I’ve done one past paper each for the first two, and overall I’m fairly confident, although there are some pretty major gaps in my Thermodynamic knowledge (how do you work out entropy change again?!), which I’m desperately trying to plug. I’ve done some revision in the other areas too, so I’m feeling fairly alright with differential equations, and statistics is just a retread of A Level stats anyway, for the most part.

First exam is on the 28th, so things are moving on.

Went camping last weekend, may or may not do a writeup on that at some point, possibly when I run out of ways to continue procrastinating. Should have struck while the iron was hot.

How’d they let this one through?

Utter madness.

With thanks to New Scientist for publishing this!

The best part is going through the formulae, as it’s patently obvious that they make no sense at all.

Wow. Sometimes work really is worth doing.

So today I sat down with the intention of figuring out how to solve ∇²u = 0, otherwise known as the Laplace equation, in spherical polar co-ordinates. Because it’s part of my course.

It may sound as a task somewhat obscure, but it’s really not. It governs any kind of potential, like gravitational, or fluid, or electrical, whatever.

Solving the equation in spherical polar co-ordinates gives insight into any problems in which potentials are important in a spherical environment, like the hydrogen atom. As it turns out, the various solutions to this equation are what create the energy levels in atoms, what makes a metal like copper behave differently from a gas like argon. It’s kinda fascinating that you are just going in solving this equation, and this kind of really fundamental stuff just leaps out of the mathematics.

Like the basis of energy levels is that a component of this differential equation has a series solution, a long chain of terms. If this chain of terms is allowed to go off to infinity, it’ll be unbounded – the sum of the series will itself be infinite. So you have to impose an artificial cut-off to the sequence for the solution to exist. The series of terms has to be finite. The really odd part is then this cut-off number, known as L, actually is something physical.

If you ever studied chemistry, you’ll know about s, p, d, and f orbitals, and how different numbers of electrons can fit in each. Well, if an electron is in the p orbital, then the L number I mentioned is 1. d, the L number is 2. You can probably guess what f is!

The reason that chemistry is the way it is all falls out of the solutions to this kind of equations. That really boggles my mind that the way the world is seems to be an inevitable result of the equations that govern it. Amazing.

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